package com.corn.filter;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.IOException;
@WebFilter("/download.jsp")
public class DownloadFilter implements Filter {
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {

    }

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
//        控制资源的访问权限
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response  = (HttpServletResponse) servletResponse;
        HttpSession session = request.getSession();
        String name = (String) session.getAttribute("name");
        if (name == null){
//            不是登录状态
            response.sendRedirect("/login.jsp");
        }else{
            filterChain.doFilter(servletRequest,servletResponse);
        }
    }

    @Override
    public void destroy() {

    }
}
